1. Borish's Clinical refraction;Benjamin,2006
2. Clinical procedures for ocular examination;Carlson,2004
3. Clinical procedures in optometry;Eskridge,1991
4. Primary care optometry;Grosvenor,2002
5. A longitudinal study of corneal astigmatism and total astigmatism;Baldwin;American Journal of Optometry and Physiological Optics,1981